<template>
  <div>
    <!-- 评论列表 -->
    <div
      class="cmt-list"
      :class="{
        'art-cmt-container-1': isShow,
        'art-cmt-container-2': !isShow,
      }"
    >
    <!-- 加载更多 -->
      <van-list
        v-model="loading"
        :finished="finished"
        finished-text="没有更多了"
        @load="onLoad"
      >
        <!-- 评论的 Item 项 -->
        <div class="cmt-item" v-for="obj in commentsList" :key="obj.com_id">
          <!-- 头部区域 -->
          <div class="cmt-header">
            <!-- 头部左侧 -->
            <div class="cmt-header-left">
              <img :src="obj.aut_photo" alt="" class="avatar" />
              <span class="uname">{{ obj.aut_name }}</span>
            </div>
            <!-- 头部右侧 -->
            <div class="cmt-header-right">
              <!-- 要点赞 -->
              <van-icon
                name="like"
                size="16"
                color="red"
                v-if="obj.is_liking === true"
                @click="isShowFn(true, obj)"
              />
              <!-- 要取消点赞 -->
              <van-icon
                name="like-o"
                size="16"
                color="gray"
                v-else
                @click="isShowFn(false, obj)"
              />
            </div>
          </div>
          <!-- 主体区域 -->
          <div class="cmt-body" v-html="obj.content"></div>
          <!-- 尾部区域 -->
          <div class="cmt-footer">{{ getTimeFn(obj.pubdate) }}</div>
        </div>
      </van-list>
    </div>

    <div>
      <!-- 底部添加评论区域 - 1 -->
      <div class="add-cmt-box van-hairline--top" v-if="isShow">
        <van-icon name="arrow-left" size="0.48rem" @click="$router.back()" />
        <div class="ipt-cmt-div" @click="addcommentFn">发表评论</div>
        <div class="icon-box">
          <van-badge :content="totalCount || ''">
            <van-icon name="comment-o" size="0.53333334rem" @click="moveFn" />
          </van-badge>
          <van-icon name="star-o" size="0.53333334rem" />
          <van-icon name="share-o" size="0.53333334rem" />
        </div>
      </div>
      <!-- 底部添加评论区域 - 2 -->
      <div class="cmt-box van-hairline--top" v-else>
        <textarea
          placeholder="友善评论、理性发言、阳光心灵"
          @blur="blurFn"
          v-fofo
          v-model="commentText"
        ></textarea>
        <!-- 发布按钮 -->
        <van-button
          type="default"
          :disabled="commentText.length === 0"
          @click="publishFn"
          >发布</van-button
        >
      </div>
    </div>
  </div>
</template>

<script>
import {
  getCommentsApi,
  likeCommentApi,
  unLikeCommentApi,
  publishCommentApi
} from '@/api'
import * as relativeTime from 'dayjs/plugin/relativeTime'
import * as dayjs from 'dayjs'
import 'dayjs/locale/zh-cn'
dayjs.locale('zh-cn') // use locale
dayjs.extend(relativeTime)
export default {
  data () {
    return {
      commentsList: [], // 评论文章的列表
      isShow: true, // 评论的输入框的显示与隐藏
      totalCount: 0, // 评论的总数量
      commentText: '', // 评论的内容
      loading: false,
      finished: false,
      offset: null
    }
  },
  props: {
    artId: [Number, String]
  },
  created () {
    // 页面刚打开的时候调用评论列表的数据
    this.getCommrntFn()
  },
  // 事件方法
  methods: {
    onLoad () {
      // 防止页面刚打开的时候就执行created  所以只有评论列表数据里面有内容才能执行onLoad方法
      if (this.commentsList.length > 0) {
        this.getCommrntFn()
      }
    },
    // 获取评论列表
    async getCommrntFn () {
      const res = await getCommentsApi({ artId: this.$route.query.aid, offset: this.offset })
      // console.log(res)
      // 没有更多数据了 finished 改为true
      if (res.data.data.results.length === 0) {
        this.finished = true
      }
      this.offset = res.data.data.last_id
      this.commentsList = [...this.commentsList, ...res.data.data.results]
      // 评论的总数量
      this.totalCount = res.data.data.total_count
      this.loading = false
    },
    // 获取时间
    getTimeFn (dataStr) {
      var a = dayjs()
      var b = dayjs(dataStr)
      return a.to(b) // in 2 years
    },
    // 点赞 / 取消点赞切换
    async isShowFn (bool, obj) {
      if (bool === true) {
        // 红心亮着 点击了之后要取消点赞
        await unLikeCommentApi(obj.com_id)
        // console.log('取消点赞', res)
        obj.is_liking = false
      } else {
        // 灰心亮着 点击了要去点赞
        await likeCommentApi(obj.com_id)
        // console.log('点赞', res)
        obj.is_liking = true
      }
    },
    // 点击发表评论
    addcommentFn () {
      this.isShow = false
      // 进入评论输入框 拉到最下面
      this.$nextTick(() => {
        // 方式1
        // window.scrollTo(0, 99999)
        // 方式2
        // window.scrollTo(0, document.documentElement.scrollHeight - window.innerHeight)
        // 方式3
        const comList = document.querySelectorAll('.cmt-item')
        comList[comList.length - 1].scrollIntoView({ behavior: 'smooth' })
      })
    },
    // 失去焦点事件
    blurFn () {
      setTimeout(() => {
        this.isShow = true
      })
    },
    // 点击评论未读按钮 滚动到最上方
    moveFn () {
      // 滚动到点赞下面
      document
        .querySelector('.like-box')
        .scrollIntoView({ behavior: 'smooth' })
      // 让未读的数组显示的数量消失
      this.totalCount = ''
    },
    // 点击发布
    async publishFn () {
      await publishCommentApi({
        target: this.$route.query.aid,
        content: this.commentText
      })
      // console.log(res)
      // 点击完发布 1.清空文本域内容 2.让页面再回到顶端看到最新发布的内容
      this.commentText = ''
      document
        .querySelector('.like-box')
        .scrollIntoView({ behavior: 'smooth' })
      // 发布完成以后 调用评论列表的方法将刚发布的评论列表渲染到页面上
      this.getCommrntFn()
    }
  }
}
</script>

<style scoped lang="less">
// 评论列表
.cmt-list {
  padding: 10px;
  .cmt-item {
    padding: 15px 0;
    + .cmt-item {
      border-top: 1px solid #f8f8f8;
    }
    .cmt-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      .cmt-header-left {
        display: flex;
        align-items: center;
        .avatar {
          width: 40px;
          height: 40px;
          background-color: #f8f8f8;
          border-radius: 50%;
          margin-right: 15px;
        }
        .uname {
          font-size: 12px;
        }
      }
    }
    .cmt-body {
      font-size: 14px;
      line-height: 28px;
      text-indent: 2em;
      margin-top: 6px;
      word-break: break-all;
    }
    .cmt-footer {
      font-size: 12px;
      color: gray;
      margin-top: 10px;
    }
  }
}
/*美化 - 文章详情 - 底部的评论页面 */
// 外层容器
.art-cmt-container-1 {
  padding-bottom: 46px;
}
.art-cmt-container-2 {
  padding-bottom: 80px;
}
// 发布评论的盒子 - 1
.add-cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  box-sizing: border-box;
  background-color: white;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 46px;
  line-height: 46px;
  padding-left: 10px;
  .ipt-cmt-div {
    flex: 1;
    border: 1px solid #efefef;
    border-radius: 15px;
    height: 30px;
    font-size: 12px;
    line-height: 30px;
    padding-left: 15px;
    margin-left: 10px;
    background-color: #f8f8f8;
  }
  .icon-box {
    width: 40%;
    display: flex;
    justify-content: space-evenly;
    line-height: 0;
  }
}
.child {
  width: 20px;
  height: 20px;
  background: #f2f3f5;
}
// 发布评论的盒子 - 2
.cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 80px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  padding-left: 10px;
  box-sizing: border-box;
  background-color: white;
  textarea {
    flex: 1;
    height: 66%;
    border: 1px solid #efefef;
    background-color: #f8f8f8;
    resize: none;
    border-radius: 6px;
    padding: 5px;
  }
  .van-button {
    height: 100%;
    border: none;
  }
}
</style>
